Intelligent Grouting Control Method Based On Wankel Pump And Optimized Grouting Control Mechanism

At present,the development of China's western development is accelerating,and the construction of transportation infrastructure will also develop rapidly.In the process of railway and highway construction,a large number of special and deep tunnels will appear,which have the characteristics of "large buried depth,long tunnel line,high stress,strong karst,high water pressure,complex structure and frequent disasters".Grouting is the main method to change the physical and mechanical properties of the formation and to strengthen the surrounding rock.The existing equipment and methods have the following problems:(1)Piston grouting pump commonly used for grouting produces different degrees of cyclic pressure per stroke,and the output pressure fluctuates from several megapascals to ten megapascals.The grouting pulse will cause secondary damage to the fragile surrounding rock,and will affect the data of test and engineering and control accuracy.(2)The existing grouting theory models are all based on stable-grouting pressure.The pressure in the theoretical curve only changes with the characteristics of the grouted medium and the slurry.However,the actual pressure of the slurry during actrual engineering fluctuates drastically,and it is difficult to obtain theoretical diffusion results.(3)When using the piston pump for model test,the larger grouting pulse can not be consistent with the theory of stable-grouting.The use of air compressor to maintain the constant pressure of the cylinder to achieve the stable-pressure groutibng can be combined with theoretical research,but does not match the actual engineering,and can not get realistic test results.(4)The test results in the current fracture grouting model test are generally unidirectional horizontal splitting or vertical splitting,and the theoretically derived single-direction splitting pulp pulse will change the direction of geostress.(5)The current theory of penetraction grouting does not take into account the effects of gravity and inertia of slurry.Therefore,this paper developed a Wankel grouting pump that can realize stable-presure grouting based on the Lelo triangle principle,and achieved the following results:(1)Research on structural principle:Based on the Lelo triangle principle,the mechanism principle of Wankel pump is studied.The mathematical model of rotor profile and cylinder cavity profile 1s established.Different parameter Wankel pump are obtained baseden on design rules.(2)Structural research:The structure,size,material selection and processing technology of the cylinder block,rotor,crankshaft,middle partition plate,cover plate and gear seat of single-cylinder and double-cylinder Wankel pumps were designed respectively.Structure,selection of material and model of sealing system and check va ve were studied.(3)Output performance study:Mathematical model of theoretical flow,real-time volume,mechanical efficiency,hydraulic efficiency,volumetric efficiency and total efficiency of Wankel pump is proposed.The performance parameters and cavitation characteristics of SDU-1.25D-44 are tested by numerical simulation and laboratory test.(4)Control systen development:Based on the Fuzzy-PID composite control method,the SDUZJ intelligent grouting system for Wankel pump was developed,which realized the stepless speed regulation with stable-pressure of Wankel pump,and has control function of program query,data record,hazard alarm,phase data query,intelligent stable-presure control.The SDUZJ program was written using TIA Portal software.(5)Optimized grouting control method:The optimized fracture and penetraction grouting control theory under stable-presure is obtained.The control equation of fracture grouting with controllable fracture direction and distance is proposed,and the diffusion law of vertical and horizontal stable-pressure prenetraction grouting was studied under the action of slurry gravity and inertia.(6)Model test:A fracture grouting model frame with additional vertical and horizontal geostress and a layered visualized prenetrction grouting model frame are designed.The optimal grouting control theory was verified by model test and SDUZJ single-liquid control system.